flabbergast
8 years ago
1 changed files with 136 additions and 7 deletions
+ 136
- 7
tmk_core/common/chibios/sleep_led.c
View File
| @@ -1,23 +1,152 @@ | |||
| #include "ch.h" | |||
| #include "hal.h" | |||
| #include "led.h" | |||
| #include "sleep_led.h" | |||
| #if defined(KL2x) || defined(K20x) /* platform selection: familiar Kinetis chips */ | |||
| /* All right, we go the "software" way: LP timer, toggle LED in interrupt. | |||
| * Based on hasu's code for AVRs. | |||
| */ | |||
| /* Breathing Sleep LED brighness(PWM On period) table | |||
| * (64[steps] * 4[duration]) / 64[PWM periods/s] = 4 second breath cycle | |||
| * | |||
| * http://www.wolframalpha.com/input/?i=%28sin%28+x%2F64*pi%29**8+*+255%2C+x%3D0+to+63 | |||
| * (0..63).each {|x| p ((sin(x/64.0*PI)**8)*255).to_i } | |||
| */ | |||
| static const uint8_t breathing_table[64] = { | |||
| 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 2, 4, 6, 10, | |||
| 15, 23, 32, 44, 58, 74, 93, 113, 135, 157, 179, 199, 218, 233, 245, 252, | |||
| 255, 252, 245, 233, 218, 199, 179, 157, 135, 113, 93, 74, 58, 44, 32, 23, | |||
| 15, 10, 6, 4, 2, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 | |||
| }; | |||
| /* LP Timer interrupt handler */ | |||
| OSAL_IRQ_HANDLER(KINETIS_LPTMR0_IRQ_VECTOR) { | |||
| OSAL_IRQ_PROLOGUE(); | |||
| /* Software PWM | |||
| * timer:1111 1111 1111 1111 | |||
| * \_____/\/ \_______/____ count(0-255) | |||
| * \ \______________ duration of step(4) | |||
| * \__________________ index of step table(0-63) | |||
| */ | |||
| // this works for cca 65536 irqs/sec | |||
| static union { | |||
| uint16_t row; | |||
| struct { | |||
| uint8_t count:8; | |||
| uint8_t duration:2; | |||
| uint8_t index:6; | |||
| } pwm; | |||
| } timer = { .row = 0 }; | |||
| timer.row++; | |||
| // LED on | |||
| if (timer.pwm.count == 0) { | |||
| led_set(1<<USB_LED_CAPS_LOCK); | |||
| } | |||
| // LED off | |||
| if (timer.pwm.count == breathing_table[timer.pwm.index]) { | |||
| led_set(0); | |||
| } | |||
| /* Reset the counter */ | |||
| LPTMR0->CSR |= LPTMRx_CSR_TCF; | |||
| OSAL_IRQ_EPILOGUE(); | |||
| } | |||
| /* LPTMR clock options */ | |||
| #define LPTMR_CLOCK_MCGIRCLK 0 /* 4MHz clock */ | |||
| #define LPTMR_CLOCK_LPO 1 /* 1kHz clock */ | |||
| #define LPTMR_CLOCK_ERCLK32K 2 | |||
| #define LPTMR_CLOCK_OSCERCLK 3 /* output from OSC */ | |||
| /* Work around inconsistencies in Freescale naming */ | |||
| #if !defined(SIM_SCGC5_LPTMR) | |||
| #define SIM_SCGC5_LPTMR SIM_SCGC5_LPTIMER | |||
| #endif | |||
| /* Initialise the timer */ | |||
| void sleep_led_init(void) { | |||
| // we could go the 'software way' -- just enable *some* timer | |||
| // and go with callbacks | |||
| // or we could go the 'hardware way' -- and use timer output to | |||
| // pins directly | |||
| /* Make sure the clock to the LPTMR is enabled */ | |||
| SIM->SCGC5 |= SIM_SCGC5_LPTMR; | |||
| /* Reset LPTMR settings */ | |||
| LPTMR0->CSR = 0; | |||
| /* Set the compare value */ | |||
| LPTMR0->CMR = 1; // trigger on counter value (i.e. every time) | |||
| /* Set up clock source and prescaler */ | |||
| /* Software PWM | |||
| * ______ ______ __ | |||
| * | ON |___OFF___| ON |___OFF___| .... | |||
| * |<-------------->|<-------------->|<- .... | |||
| * PWM period PWM period | |||
| * | |||
| * R interrupts/period[resolution] | |||
| * F periods/second[frequency] | |||
| * R * F interrupts/second | |||
| */ | |||
| /* === OPTION 1 === */ | |||
| // for 1kHz LPO | |||
| // No prescaler => 1024 irqs/sec | |||
| // LPTMR0->PSR = LPTMRx_PSR_PCS(LPTMR_CLOCK_LPO)|LPTMRx_PSR_PBYP; | |||
| /* === OPTION 2 === */ | |||
| // for nMHz IRC (n=4 on KL25Z, KL26Z and K20x; n=2 or 8 on KL27Z) | |||
| MCG->C2 |= MCG_C2_IRCS; // fast (4MHz) internal ref clock | |||
| #if defined(KL27Z) // divide the 8MHz IRC by 2, to have the same MCGIRCLK speed as others | |||
| MCG->MC |= MCG_MC_LIRC_DIV2_DIV2; | |||
| #endif /* KL27Z */ | |||
| MCG->C1 |= MCG_C1_IRCLKEN; // enable internal ref clock | |||
| // to work in stop mode, also MCG_C1_IREFSTEN | |||
| // Divide 4MHz by 2^N (N=5) => 62500 irqs/sec => | |||
| // => approx F=61, R=256, duration = 4 | |||
| LPTMR0->PSR = LPTMRx_PSR_PCS(LPTMR_CLOCK_MCGIRCLK)|LPTMRx_PSR_PRESCALE(5); | |||
| /* === OPTION 3 === */ | |||
| // for OSC output (external crystal), usually 8MHz or 16MHz | |||
| // OSC0->CR |= OSC_CR_ERCLKEN; // enable ext ref clock | |||
| // to work in stop mode, also OSC_CR_EREFSTEN | |||
| // Divide by 2^N | |||
| // LPTMR0->PSR = LPTMRx_PSR_PCS(LPTMR_CLOCK_OSCERCLK)|LPTMRx_PSR_PRESCALE(7); | |||
| /* === END OPTIONS === */ | |||
| /* Interrupt on TCF set (compare flag) */ | |||
| nvicEnableVector(LPTMR0_IRQn, 2); // vector, priority | |||
| LPTMR0->CSR |= LPTMRx_CSR_TIE; | |||
| } | |||
| void sleep_led_enable(void) { | |||
| led_set(1<<USB_LED_CAPS_LOCK); | |||
| /* Enable the timer */ | |||
| LPTMR0->CSR |= LPTMRx_CSR_TEN; | |||
| } | |||
| void sleep_led_disable(void) { | |||
| led_set(0); | |||
| /* Disable the timer */ | |||
| LPTMR0->CSR &= ~LPTMRx_CSR_TEN; | |||
| } | |||
| void sleep_led_toggle(void) { | |||
| // not working yet, state not saved anywhere currently | |||
| /* Toggle the timer */ | |||
| LPTMR0->CSR ^= LPTMRx_CSR_TEN; | |||
| } | |||
| #else /* platform selection: not on familiar Kinetis chips */ | |||
| void sleep_led_init(void) { | |||
| } | |||
| void sleep_led_enable(void) { | |||
| led_set(1<<USB_LED_CAPS_LOCK); | |||
| } | |||
| void sleep_led_disable(void) { | |||
| led_set(0); | |||
| } | |||
| void sleep_led_toggle(void) { | |||
| // not implemented | |||
| } | |||
| #endif /* platform selection */ | |||